The 43-year-old Kevin Reynolds admitted punching Ferguson in the groin before head butting a police community support officer in central London.

Adeola Olowu, the man's defendant, said Reynolds didn't know it was Ferguson and that he was joking.

"I do not think Sir Alex Ferguson saw this as a joke," Magistrate Daphne Wickham said.

Reynolds, was remanded in custody, has been warned he could be jailed.